Bluetooth tester provides EDR, AFH testing

As the Bluetooth wireless phenomena becomes all-pervasive, more designers are compelled to adopt the technology. But the complexity of the protocol and the difficulty of working with RF at 2.4GHz can present challenges and struggles.

Test costs can be high, which isn't what you want in a Bluetooth-equipped end-product that often has to carry a price tag that's attractive to consumers. Poorly prepared microwave cabling and connectors can contribute to uncertainty. When it finally comes to functional test, you may be in for some unpleasant surprises.

Traceable to standardsThe MT8852B Bluetooth test set from Anritsu Corp. provides both Enhanced Data Rate (EDR) and Adaptive Frequency Hopping (AFH) testing. Going beyond the predecessor MT8852A, the MT8852B uses the same user interface but supports EDR test cases. It also supports all three codec air interfaces: µ-law, A-law and Continuously Variable Slope Delta (CVSD), on up to three audio channels. Rear-panel connectors support analogue I/O for all three of these audio channels.

Enhances scriptsThe MT8852B adds the EDR measurements to existing scripts so that you can test EDR chips with a single press of the box's RUN key. The MT8852B also gives you pi4-DQPSK and 8DPSK signal generator, and a modulation analyser. The MT8852B automatically performs these measurements on he appropriate packets.

With these features, the MT8852B now supports TP/TRM/CA/10/C the EDR relative transmit power test case, as well as TP/TRM/CA/11/C, the EDR carrier frequency stability and modulation accuracy test case. The EDR relative transmit power test case ensures that the difference in average transmit power during the frequency-modulated and phase-modulated parts of a packet is within range.

The carrier stability test case requires the measurement of the initial packet frequency error, as well as the frequency error of the payload broken down into 50µs blocks. The MT8852B automates this test, and you can set the number of payload blocks tested.

The MT8852B also supports TP/TRM/CA/12/C, the EDR differential phase encoding and TP/TRM/CA/13/C EDR in-band spurious emissions test cases (in conjunction with a spectrum analyser such as Anritsu's MS2681A). The differential phase measurement transmits a packet with a defined PRBS9 payload. For each packet received the payload is demodulated and compared with a defined ideal packet. The goal is to give a resultant symbol error value.

The test set also supports the TP/RCV/CA/07/C EDR sensitivity test case, as well as the TP/RCV/CA/08/C EDR BER (bit error rate) floor performance test case.

The MT8852B supports the EDR dirty transmitter requirements for signal impairments made during receiver sensitivity testing. The unit's EDR Sensitivity display shows BER in exponential format as defined in the test spec, as well as packet error rate and the number of packets tested.

Finally, the MT8852B also runs the TP/RCV/CA/09/C C/I performance test case (you'll need two MT8852Bs for this), as well as the TP/RCV/CA/10/C EDR maximum input level test case.

Free Windows waresAnritsu's press statement also refers to its free BlueTest production software. Running on a PC, BlueTest is what automates test scripts and handles archival storage of results. You also get source code for BlueTest, written in VisualBASIC, so that you can to customize your test programs. In use, BlueTest executables control up to sixteen MT8852B units, using the IEEE-488.2/GPIB (General Purpose Interface Bus).

What is Bluetooth technology?
A technology for wireless personal area networks, which provides a way to connect and exchange information between devices such as cell phones, laptops, PCs and digital cameras via a short range radio frequency.